Method and terminal for counting preamble retransmission in random access procedure

ABSTRACT

The present disclosure provide a method and terminal for counting preamble retransmission in a random access procedure. The method includes: in a random access procedure, when detecting that no Random Access Response (RAR) is received or contention resolution fails, counting a number of times of retransmission of a preamble and/or a number of times of power ramping of transmission of the preamble according to a configured counter/counters.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit and priority of Chinese ApplicationNo. 201710459794.1, filed on Jun. 16, 2017, which is incorporated byreference in its entirety.

TECHNICAL FIELD

The present disclosure relates to the field of communication technology,and more particularly to a method and terminal for counting preambleretransmission in a random access procedure.

BACKGROUND

A Random Access Channel (RACH) is an uplink transmission channel. TheRACH is received in the whole cell and the RACH is usually used toperform PAGING reply and Mobile Station (MS) originating call/loginaccess, etc.

Trigger conditions of the random access include: (1) RRC_IDLE initialaccess; (2) initial access when the wireless link is disconnected; (3)random access is required during switching; (4) the random accessprocedure is required in RRC_CONNECTED state and when Downlink (DL) datais received, for example, when a Uplink (UL) synchronization state is“asynchronous”; (5) the random access procedure is required inRRC_CONNECTED state and when UL data is received, for example, when a ULsynchronization state is “asynchronous” or there is no PUCCH resourceavailable for scheduling.

The random access procedures include a contention-free based randomaccess procedure and a contention based random access procedure.

The contention-free based random access procedure includes two steps:

1. a User Equipment (UE) transmits to a base station a random accesspreamble, which is also referred as msg.1;

2. the UE receives from the base station a Random Access Response (RAR),which is also referred as msg.2.

The contention based random access procedure includes following steps:

1. a User Equipment (UE) transmits to a base station a random accesspreamble, which is also referred as msg.1;

2. the UE receives from the base station a Random Access Response (RAR),which is also referred as msg.2.

3. the UE transmits to the base station a contention resolution request,which is also referred as msg.3;

4. the UE receives from the base station a contention resolution result,which is also referred as msg.4.

In the fifth-Generation (5G) New Radio (NR) system, in the design of thecurrent random access, each re-transmission of the random accesspreamble supports power ramping.

In the Long Term Evolution (LTE) system, a preamble transmissioncounter, i.e., PREAMBLE_TRANSMISSION_COUNTER is used to count a numberof times of preamble retransmission and used to perform power ramping.

Each time the random access procedure is initialized, the counter isreset to 1.

When the msg.2, i.e., RAR is not correctly received and a power rampingsuspension instruction transmitted from an underlying physical layer isnot received, the counter adds 1.

When the contention resolution fails and the power ramping suspensioninstruction transmitted from the underlying physical layer is notreceived, the counter adds 1.

In the above processes, when the value of the counter reaches a maximumnumber of times of preamble retransmission plus 1, the Media AccessControl (MAC) layer notifies an upper layer of the random access problemor the random access failure.

The power of each preamble transmission is calculated using thefollowing formula according to the step size of the counter and thepower ramping:

PREAMBLE_RECEIVED_TARGET_POWER=preambleInitialReceivedTargetPower+DELTA_PREAMBLE+(PREAMBLE_TRANSMISSION_COUNTER−1)*powerRampingStep; where PREAMBLE_RECEIVED_TARGET_POWER denotes atarget power value, preambleInitialReceivedTargetPower denotes anoriginal power value, DELTA_PREAMBLE denotes a preset fixed value,PREAMBLE_TRANSMISSION_COUNTER denotes the value of a current preambletransmission counter and powerRampingStep denotes the step size of thepower ramping.

In the LTE, the same counter is used to count the power climb and thenumber of times of preamble transmission. In other words, the preambletransmission counter is used to count both the number of times of powerramping and the number of times of preamble transmission.

The introduction of the Massive Multiple Input Multiple Output (MIMO)antenna in the 5G NR system gives the concept of beam. The UE can choosea different beam to transmit the preamble each time the preamble isre-transmitted. The current conclusion is that when the UE performs beamswitching, the count for the power ramping remains unchanged. When theUE does not change the beams during each re-transmission, the count forthe power ramping increases. Therefore, the existing single counter thatis used for counting both the power ramping and preamble transmissioncannot work. That is, the existing single counter cannot meet thefunctions of counting both the power ramping and preamble transmission,and cannot guarantee the reliability of communication of the NR system.

SUMMARY

Embodiments of the present disclosure provide a method for countingpreamble retransmission in a random access procedure, including:

in a random access procedure, when detecting that no Random AccessResponse (RAR) is received or contention resolution fails, counting anumber of times of retransmission of a preamble and/or a number of timesof power ramping of transmission of the preamble according to aconfigured counter/counters.

Embodiments of the present disclosure further provide a terminal,including:

a processing module configured to, in a random access procedure, whendetecting that no Random Access Response (RAR) is received or contentionresolution fails, counting a number of times of retransmission of apreamble and/or a number of times of power ramping of transmission ofthe preamble according to a configured counter/counters.

Embodiments of the present disclosure further provide a terminal,including: a storage, processor and computer programs which are storedin the storage and run on the processor. The computer programs areexecuted by the processor to implement steps of the above method forcounting preamble retransmission in a random access procedure.

Embodiments of the present disclosure further provide a computerreadable storage medium including computer programs stored therein. Thecomputer programs are executed by the processor to implement steps ofthe above method for counting preamble retransmission in a random accessprocedure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flow chart illustrating a method for counting preambleretransmission in a random access procedure according to variousembodiments of the present disclosure;

FIG. 2 is a diagram illustrating modules of a terminal according tovarious embodiments of the present disclosure; and

FIG. 3 is a diagram illustrating structure of a terminal according tovarious embodiments of the present disclosure.

DETAILED DESCRIPTION

The present disclosure will be described in details hereinafter withreference to accompanying drawings and embodiments to make theobjective, technical solutions and merits therein clearer.

As for the problem of being unable to simultaneously satisfy thefunctions of counting the power ramping and preamble transmission andguarantee the reliability of the communication of the NR system when asingle counter is used for counting both the power ramping and preambletransmission, embodiments of the present disclosure provides a methodand terminal for counting preamble retransmission in a random accessprocedure.

As shown in FIG. 1, the method for counting preamble retransmission in arandom access procedure in embodiments of the present disclosureincludes:

Block 101, in a random access procedure, when detecting that no RandomAccess Response (RAR) is received or contention resolution fails,counting a number of times of preamble retransmission and/or a number oftimes of power ramping of preamble transmission according to aconfigured counter/counters.

It should be noted that the counters in embodiments of the presentdisclosure may include a preamble transmission counter configured forthe UE, i.e., PREAMBLE_TRANSMISSION_COUNTER, a beam preamblere-transmission counter configured for the beam, i.e.,PREAMBLE_TRANSMISSION_COUNTER_BEAM, a power ramping counter configuredfor the power ramping, i.e., POWER_RAMPING_COUNTER, a preamblere-transmission beam switching counter configured for the beamswitching, i.e., PREAMBLE_BEAM_SWITCH_COUNTER and a power level preambletransmission counter configured for the power level, i.e.,PREAMBLE_TRANSMISSION_COUNTER_PL. It should be noted that the preambletransmission counter, the beam preamble re-transmission counter, thepower ramping counter and the preamble re-transmission beam switchingcounter (or the power level preamble transmission counter) belong todifferent types of counters and the preamble re-transmission beamswitching counter and the power level preamble transmission counter arecounters that cannot exist simultaneously.

Each counter is described in details hereinafter respectively accordingto the types of the counters configured in the terminal.

First, only one type of counter is configured in the terminal

when only one type of counter is configured in the terminal and no RARmessage is received or the contention resolution fails, the counter adds1; or,

when no RAR message is received or the contention resolution fails, andwhen a power ramping suspension instruction which is used to instruct aMedium Access Control (MAC) layer by a physical layer is not received,the counter adds 1.

1. Only the preamble transmission counter is configured in the terminal

The preamble transmission counter is configured for each terminal, thatis, each terminal includes only one preamble transmission counter. Whenthe preamble transmission counter is initialized or reset in each randomaccess procedure, the preamble transmission counter is reset to 1 or 0.Further, when the RAR message is not received in preset time or thecontention resolution fails, the preamble transmission counter adds 1.It should be noted that the preset time period refers to an RAR window,i.e., an RAR time window.

When a count value of the preamble transmission counter reaches a firstpreset maximum number of times of transmission Max1 or Max1+1, the upperlayer is notified of a random access problem or failure of the randomaccess procedure (i.e., random access failure) via the MAC layer.

It should be noted that the upper layer refers to a Radio Link Control(RLC) layer, a Radio Resource Control (RRC) layer, a network layer or anapplication layer etc., on the physical layer.

It should be noted that in this situation, the situation for configuringthe power ramping of the random access preamble retransmission includes:

when the preamble transmission counter counts the preambleretransmission,

when two adjacent transmissions of the preamble use a same beam, addingone step size to a transmission power; or,

when the two adjacent transmissions of the preamble use the same beamand the power ramping suspension instruction which is used to instructthe MAC layer by the physical layer is not received, adding one stepsize to the transmission power;

otherwise, keeping the transmission power unchanged.

The step size is configured by the base station for the terminal (thebase station configures the step size for the terminal via a dedicatedRadio Resource Control (RRC) message, RRC configuration, RRCre-configuration, System Information (SI) or a broadcast message, etc.)or determined according to a preset rule (i.e., a protocol).

It should be noted that in the power ramping process, when an obtainedtransmission power is larger than or equals the maximum transmissionpower, the method further includes:

transmitting, by the terminal, the preamble according to the maximumpower; and/or

instructing power ramping suspension.

It should be noted that the power ramping suspension instruction is usedto instruct the MAC layer by the physical layer of the terminal. Theremay be other physical layer triggering conditions for the power rampingsuspension instruction, such as when temporarily dropping a randomaccess procedure (this scenario may occur when the random accessconflicts).

2. Only the beam preamble retransmission counter is configured in theterminal

The beam preamble retransmission counter is configured for the beam,that is, the terminal may include only one beam preamble retransmissioncounter and also may include multiple beam preamble retransmissioncounters (that is, one beam preamble retransmission counter may beconfigured for each beam and one beam preamble re-transmission countermay be configured for some beams). Each time the random access procedureis initialized or reset, the beam preamble retransmission counter isreset to 1 or 0.

The count rule of the beam preamble retransmission counter may beconfigured using following one or multiple modes.

1) When the random access preamble is transmitted on a first beam and noRAR message is received in preset time, a beam preamble retransmissioncounter configured based on the first beam adds 1.

That is, the random access preamble (i.e., msg. 1) is transmitted on abeam. When no RAR message is received in the RAR window, the count valueof the beam preamble retransmission counter corresponding to the beamadds 1.

2) When a random access message three (i.e., msg. 3, i.e., a message,which is transmitted to the base station by the terminal in the randomaccess procedure and is relevant to the scheduling transmission) istransmitted on a second beam and the contention resolution fails, a beampreamble retransmission counter configured based on the second beam adds1.

That is, the terminal transmits the msg. 3 on a beam. When thecontention resolution fails, the beam preamble retransmission countercorresponding to the beam adds 1.

3) When the random access preamble is transmitted on a third beam, therandom access message three is transmitted on a fourth beam and thecontention resolution fails, a beam preamble retransmission counterconfigured based on the third beam adds 1.

That is, the msg. 1 is transmitted on one beam and the msg. 3 (the beamof which may be the same as or may be different from that of the msg. 1)is transmitted on another beam. When the contention resolution fails,the beam preamble retransmission counter corresponding to the beam,which is used to transmit the msg. 1, adds 1.

4) When the random access preamble is transmitted on the third beam, therandom access message three is transmitted on a fourth beam and thecontention resolution fails, the beam preamble retransmission counterconfigured based on the third beam and a beam preamble retransmissioncounter configured based on the fourth beam respectively add one.

That is, the msg. 1 is transmitted on one beam and the msg. 3 (the beamof which may be the same as or may be different from that of the msg. 1)is transmitted on another beam. When the contention resolution fails,the beam preamble retransmission counter corresponding to the beam,which is used to transmit the msg. 1, and the beam preambleretransmission counter corresponding to the beam, which is used totransmit the msg. 3, respectively add one.

It should be noted that the above 2), 3) and 4) situations are parallelsituations and one of the above situations may be chosen in use.

It should be noted that when a count value of the beam preambleretransmission counter reaches a second preset maximum number of timesof transmission Max2 or Max2+1, the method further includes:

when a next retransmission of the random access preamble is performed inthis random access procedure, switching beams; or,

when the next retransmission of the random access preamble is performedin this random access procedure, removing a beam, which is used toperform previous transmission of the random access preamble, fromcandidate beams for next retransmission of the random access preamble;or,

notifying an upper layer of a random access problem or failure of therandom access procedure via the MAC layer.

Specifically, when the next retransmission of the random access preambleis performed in this random access procedure, the first implementationmode for removing the beam, which is used to perform the previoustransmission of the random access preamble from the candidate beams forthe next retransmission of the random access preamble, includes:

in preset time or preset number of times, removing the beam, which isused to perform the previous transmission of the random access preamblefrom the candidate beams for the next retransmission of the randomaccess preamble.

That is, when the count value of the beam preamble retransmissioncounter reaches the preset maximum value, in the preset time or presetnumber of times of retransmission, the beam, which is used to performthe previous retransmission, is no longer used to perform the nextretransmission.

In the first implementation, when reaching the preset time or presetnumber of times, the terminal may select restarting the beam preambleretransmission counter.

Specifically, when the next retransmission of the random access preambleis performed in this random access procedure, the second implementationmode of removing the beam, which is used to perform the previoustransmission of the random access preamble from the candidate beams forthe next retransmission of the random access preamble, includes:

when transmission powers of the terminal are in a same power level or apreset number of power levels, removing the beam, which is used toperform the previous transmission of the random access preamble from thecandidate beams for the next retransmission of the random accesspreamble.

That is, when the count value of the beam preamble retransmissioncounter reaches the maximum value, in the same power level or the presetnumber of power levels, the beam, which is used to perform the previousretransmission, is no longer used to perform next retransmission.

In the first implementation, when the transmission powers of theterminal exceed the same power level or the preset number of powerlevels, the terminal may select to restart the beam preamblere-transmission counter.

When multiple beam preamble retransmission counters exist in theterminal, the specific usage situations of the multiple beam preambleretransmission counter includes:

1) when count values of a first preset number of beam preambleretransmission counters reach a third preset maximum number of times oftransmission Max3 or Max3+1, notifying an upper layer of a random accessproblem or failure of the random access procedure via the MAC layer.

The first preset number refers to a number of beam preambleretransmission counters corresponding to all beams of the terminal orrefers to a number of beam preamble retransmission counterscorresponding to some beams of the terminal.

2) When a sum of count values of a second preset number of beam preambleretransmission counters reaches the third preset maximum number of timesof transmission Max3 or Max3+1, notifying an upper layer of a randomaccess problem or failure of the random access procedure via the MAClayer.

The second preset number refers to a number of beam preambleretransmission counters corresponding to all beams of the terminal orrefers to a number of beam preamble retransmission counterscorresponding to some beams of the terminal.

It should be noted that in this situation, the configuration situationof power ramping of retransmission of the random access preambleincludes:

when two adjacent transmissions of the preamble use a same beam, addingone step size to a transmission power; or,

when the two adjacent transmissions of the preamble use the same beamand the power ramping suspension instruction which is used to instructthe MAC layer by the physical layer is not received, adding one stepsize to the transmission power;

otherwise, keeping the transmission power unchanged.

The step size is configured by the base station for the terminal ordetermined according to a preset rule.

It should be noted that in the power ramping process, when an obtainedtransmission power is larger than or equals the maximum transmissionpower, the method further includes:

transmitting, by the terminal, the random access preamble according tothe maximum power.

3. Only the power ramping counter is configured in the terminal

The power ramping counter is configured for a number of times of thepower ramping. The power ramping counter is reset to 1 or 0 each timethe random access procedure is initialized or reset.

Specifically, when any of not correctly receiving the RAR message inpreset time, failure of contention resolution and retransmission of thepreamble occurs and two adjacent transmissions of the preamble use asame beam, the power ramping counter adds 1; or,

when any of not correctly receiving the RAR message in the preset time,failure of contention resolution and retransmission of the preambleoccurs, two adjacent transmissions of the preamble use the same beam andthe power ramping suspension instruction which is used to instruct theMAC layer by the physical layer is not received, the power rampingcounter adds 1.

It should be noted that one power ramping counter may be configured foreach terminal and the power ramping counter may be configured for thebeam. When the power ramping counter is configured for the beam, thepower ramping counter is configured based on a single beam and the beamsare switched at each re-transmission, the power ramping countercorresponding to the current beam is reset to a value of the powerramping counter corresponding to a transmission beam, which is used toperform the previous transmission of the random access preamble, whichguarantees that when the terminal switches the beams, the value of thepower ramping counter remains unchanged.

It should be noted that in this situation, the configuration situationof power ramping of the retransmission of the random access preambleincludes:

obtaining a transmission power of retransmission after ramping accordingto a formulaPREAMBLE_RECEIVED_TARGET_POWER=preambleInitialReceivedTargetPower+DELTA_PREAMBLE+(POWER_RAMPING_COUNTER−1)* powerRampingStep;

where PREAMBLE_RECEIVED_TARGET_POWER denotes a target power value,preambleInitialReceivedTargetPower denotes an original power value,DELTA_PREAMBLE denotes a preset fixed value, POWER_RAMPING_COUNTERdenotes a value of the current power ramping counter andpowerRampingStep denotes a power ramping step size;

the power ramping step size is configured by the base station for theterminal (the base station configures the step size for the terminal viaa dedicated Radio Resource Control (RRC) message, RRC configuration, RRCre-configuration, System Information (SI) or a broadcast message, etc.)or determined by a preset rule (i.e., a protocol).

It should be noted that in the power ramping process, when atransmission power obtained via calculation is larger than or equals themaximum power, the method further includes:

transmitting, by the terminal, the random access preamble according tothe maximum power.

It should be noted that when a count value of the power ramping counterreaches the maximum number or the maximum number plus 1 and when notcorrectly receiving the RAR messages or contention resolution failureoccurs for a preset number of times in the present time, an upper layeris notified of a random access problem or failure of the random accessprocedure via the MAC layer.

4. Only a preamble retransmission beam switching counter or a powerlevel preamble transmission counter are configured in the terminal

The preamble retransmission beam switching counter or power levelpreamble transmission counter is reset to 1 or 0 each time the randomaccess procedure is initialized or reset. When beams are switched whenthe random access preamble is re-transmitted, the preambleretransmission beam switching counter or power level preambletransmission counter adds 1.

When the preamble retransmission beam switching counter or power levelpreamble transmission counter reaches the preset maximum number Max4 orMax4+1, one of the following processes is executed:

1) performing power ramping when re-transmitting the random accesspreamble and resetting the preamble retransmission beam switchingcounter or power level preamble transmission counter;

2) at next retransmission of the random access preamble, keeping beamsun-switched; or

3) at the next retransmission of the random access preamble, switchingto a beam, which has not been used to transmit the random accesspreamble, to re-transmit the random access preamble.

It should be noted that an implementation mode of switching to the beam,which has not been used to transmit the random access preamble, tore-transmit the random access preamble includes:

switching to a beam that is in a same power level or preset number ofpower levels with the current beam and has not been used to transmit therandom access preamble, to re-transmit the random access preamble.

It should be noted that when the transmission power used by the terminalfor transmitting the preamble changes, the preamble retransmission beamswitching counter or power level preamble transmission counter requireto be reset.

Specifically, when the preamble retransmission beam switching counter orpower level preamble transmission counter reaches the maximum countvalue and a current transmission power of the terminal reaches themaximum transmission power, an upper layer is notified of a randomaccess problem or failure of the random access procedure via the MAClayer.

Second, at least two types of counters are configured in the terminal

When at least two types of counters are configured in the terminal, whenthe counters reach the maximum counting quantities, an upper layer isnotified of a random access problem or failure of the random accessprocedure via the MAC layer.

1. The terminal is configured with a preamble transmission counter and abeam preamble retransmission counter.

It should be noted that when the preamble transmission counter and thebeam preamble retransmission counter are initialized or reset in eachrandom access procedure, both the preamble transmission counter and thebeam preamble retransmission counter are reset to 1 or 0.

The count rule of the beam preamble retransmission counter is configuredvia one or multiple of the following modes.

1) When the random access preamble is transmitted on a first beam and noRAR message is received in preset time, a beam preamble retransmissioncounter configured based on the first beam adds 1.

2) When a random access message three (i.e., msg. 3, i.e., the message,which is transmitted to the base station from the terminal and isassociated with the scheduling transmission in the random accessprocedure) is transmitted on a second beam and when the contentionresolution fails, the beam preamble retransmission counter configuredbased on the second beam adds 1.

3) When the random access preamble is transmitted on a third beam, therandom access message three is transmitted on a fourth beam and thecontention resolution fails, a beam preamble retransmission counterconfigured based on the third beam adds 1.

4) When the random access preamble is transmitted on the third beam, therandom access message three is transmitted on the fourth beam and thecontention resolution fails, the beam preamble retransmission counterconfigured based on the third beam and a beam preamble retransmissioncounter configured based on the fourth beam respectively add 1.

It should be noted that the above 2), 3) and 4) situations are parallelsituations and one of the above situations may be chosen in use.

In this situation, when a count value of the beam preambleretransmission counter reaches a second preset maximum number of timesof transmission Max2 or Max2+1, the method further includes:

when next retransmission of the random access preamble is performed inthis random access procedure, switching beams;

when the next retransmission of the random access preamble is performedin this random access procedure, removing a beam, which is used toperform previous transmission of the random access preamble fromcandidate beams for the next retransmission of the random accesspreamble; or

notifying an upper layer of a random access problem or failure of therandom access procedure via the MAC layer.

It should be noted that in this situation, the configuration situationof power ramping of the retransmission of the random access preambleincludes:

when two adjacent transmissions of the preamble use a same beam, addingone step size to the transmission power; or

when the two adjacent transmissions of the preamble use the same beamand the power ramping suspension instruction which is used to instructthe MAC layer by the physical layer is not received, adding one stepsize to the transmission power;

otherwise, keeping the transmission power unchanged.

The step size is configured by the base station for the terminal ordetermined according to a preset rule.

It should be noted that in the power ramping process, when an obtainedtransmission power is larger than or equals the maximum transmissionpower, the method further includes:

transmitting, by the terminal, the random access preamble according tothe maximum power.

In this situation, when the count value of the preamble transmissioncounter reaches a first preset maximum number of times of transmissionMax1 or Max1+1, an upper layer is notified of a random access problem orfailure of the random access procedure via the MAC layer;

when count values of a first preset number of beam preambleretransmission counters reach a third preset maximum number of times oftransmission Max3 or Max3+1, the upper layer is notified of the randomaccess problem or the failure of the random access procedure via the MAClayer; or

when a sum of count values of a second preset number of beam preambleretransmission counters reaches the third preset maximum number of timesof transmission Max3 or Max3+1, the upper layer is notified of therandom access problem or the failure of the random access procedure viathe MAC layer.

2. A preamble transmission counter and a power ramping counter areconfigured in the terminal

It should be noted that when the preamble transmission counter and thepower ramping counter are initialized or reset in each random accessprocedure, both the preamble transmission counter and the power rampingcounter are reset to 1 or 0.

Specifically, when the RAR message is not correctly received in presettime or the contention resolution fails, the preamble transmissioncounter adds 1.

Further, when a count value of the preamble transmission counter reachesa first preset maximum number of times of transmission Max1 or Max1+1,an upper layer is notified of a random access problem or failure of therandom access procedure via the MAC layer.

Optionally, the power ramping of the retransmission of the random accesspreamble is configured using following modes:

when the preamble transmission counter counts the preambleretransmission,

when two adjacent transmissions of the preamble use a same beam, addingone step size to a transmission power; or

when the two adjacent transmissions of the preamble use the same beamand the power ramping suspension instruction which is used to instructthe MAC layer by the physical layer is not received, adding one stepsize to the transmission power;

otherwise, keeping the transmission power unchanged.

The step size is configured by the base station for the terminal ordetermined according to a preset rule.

In this situation, the configuration situation of the power rampingcounter includes:

when any of not correctly receiving the RAR message, contentionresolution failure and retransmission of the preamble occurs in thepreset time and two adjacent transmissions of the preamble use a samebeam, adding 1 to the power ramping counter; or

when any of not correctly receiving the RAR message, contentionresolution failure and retransmission of the preamble occurs in thepreset time, two adjacent transmissions of the preamble use the samebeam and the power ramping suspension instruction which is used toinstruct the MAC layer by the physical layer is not received, adding 1to the power ramping counter.

It should be noted that when the power ramping counter is configuredbased on a single beam and when the beams are switched at eachretransmission, the value of the power ramping counter corresponding tothe current beam is reset to that of the power ramping countercorresponding to a transmission beam, which is used to perform theprevious transmission of the random access preamble.

Therefore, in this situation, when the terminal has the power rampingcounter and when the ramping power is determined, following modes arepreferred:

obtaining a transmission power of retransmission after ramping accordingto a formulaPREAMBLE_RECEIVED_TARGET_POWER=preambleInitialReceivedTargetPower+DELTA_PREAMBLE+(POWER_RAMPING_COUNTER−1)* powerRampingStep;

where PREAMBLE_RECEIVED_TARGET_POWER denotes a target power value,preambleInitialReceivedTargetPower denotes an original power value,DELTA_PREAMBLE denotes a preset fixed value, POWER_RAMPING_COUNTERdenotes a value of the current power ramping counter andpowerRampingStep denotes a power ramping step size;

the power ramping step size is configured by the base station for theterminal or determined by a preset rule.

In this situation, when a transmission power obtained via calculation islarger than or equals the maximum power, the method further comprises:

transmitting, by the terminal, the random access preamble according tothe maximum power.

3. A beam preamble retransmission counter and a power ramping counterare configured in the terminal

It should be noted that when the beam preamble retransmission counterand power ramping counter are initialized or reset in each random accessprocedure, both the beam preamble retransmission counter and powerramping counter are reset to 1 or 0.

The configuration situation of the beam preamble retransmission counterincludes:

when the random access preamble is transmitted on a first beam and theRAR message is not correctly received in the preset time, adding 1 to abeam preamble retransmission counter configured based on the first beam;

when a random access message three is transmitted on a second beam andthe contention resolution fails, adding 1 to a beam preambleretransmission counter configured based on the second beam; or

when the random access preamble is transmitted on the third beam, therandom access message three is transmitted on a fourth beam and thecontention resolution fails, adding 1 to a beam preamble retransmissioncounter configured based on the third beam, or respectively adding 1 tothe beam preamble retransmission counter configured based on the thirdbeam and a beam preamble retransmission counter configured based on thefourth beam.

Further, when a count value of the beam preamble retransmission counterreaches a second preset maximum number of times of transmission Max2 orMax2+1, the method further includes:

when next retransmission of the random access preamble is performed inthis random access procedure, switching beams;

when the next retransmission of the random access preamble is performedin this random access procedure, removing a beam, which is used toperform previous transmission of the random access preamble fromcandidate beams for next retransmission of the random access preamble;or

notifying an upper layer of a random access problem or failure of therandom access procedure via the MAC layer.

Further, when count values of a first preset number of beam preambleretransmission counters reach a third preset maximum number of times oftransmission Max3 or Max3+1, an upper layer is notified of a randomaccess problem or failure of the random access procedure via the MAClayer; or

when a sum of count values of a second preset number of beam preambleretransmission counters reach the third preset maximum number of timesof transmission Max3 or Max3+1, the upper layer is notified of therandom access problem or the failure of the random access procedure viathe MAC layer.

The specific configuration situation of the power ramping counterincludes:

when any of not correctly receiving the RAR message, contentionresolution failure and retransmission of the preamble occurs in thepreset time and two adjacent transmissions of the preamble use the samebeam, adding 1 to the power ramping counter; or

when any of not correctly receiving the RAR message, contentionresolution failure and retransmission of the preamble occurs in thepreset time, two adjacent transmissions of the preamble use the samebeam and the power ramping suspension instruction which is used toinstruct the MAC layer by the physical layer is not received, adding 1to the power ramping counter.

Further, when the power ramping counter is configured based on a singlebeam and the beams are switched at each re-transmission, the value ofthe power ramping counter corresponding to the current beam is reset tothat of the power ramping counter corresponding to a transmission beam,which is used to perform the previous transmission of the random accesspreamble.

Therefore, in this situation, when the terminal has the power rampingcounter and when the ramping power is determined, following modes arepreferred:

obtaining a transmission power of retransmission after ramping accordingto a formulaPREAMBLE_RECEIVED_TARGET_POWER=preambleInitialReceivedTargetPower+DELTA_PREAMBLE+(POWER_RAMPING_COUNTER−1)* powerRampingStep;

where PREAMBLE_RECEIVED_TARGET_POWER denotes a target power value,preambleInitialReceivedTargetPower denotes an original power value,DELTA_PREAMBLE denotes a preset fixed value, POWER_RAMPING_COUNTERdenotes a value of the current power ramping counter andpowerRampingStep denotes a power ramping step size;

the power ramping step size is configured by the base station for theterminal or determined by a preset rule.

In this mode, when an obtained transmission power is larger than orequals the maximum power, the method further includes:

transmitting, by the terminal, the random access preamble according tothe maximum power.

4. A preamble transmission counter, a beam preamble retransmissioncounter and a power ramping counter are configured in the terminal

It should be noted that when the preamble transmission counter, the beampreamble retransmission counter and the power ramping counter areinitialized or reset in each random access procedure, the preambletransmission counter, the beam preamble retransmission counter and thepower ramping counter are reset to 1 or 0.

The specific configuration situation of the preamble transmissioncounter includes:

when no RAR message is received by the preamble transmission counter inpreset time or the contention resolution fails, adding 1 to the preambletransmission counter.

Further, when a count value of the preamble transmission counter reachesa first preset maximum number of times of transmission Max1 or Max1+1,the method further includes: notifying an upper layer of a random accessproblem or failure of the random access procedure via the MAC layer.

Optionally, the power ramping of the retransmission of the random accesspreamble is configured using following modes:

when the preamble transmission counter counts preamble retransmission,

when two adjacent transmissions of the preamble use a same beam, addingone step size to a transmission power; or

when the two adjacent transmissions of the preamble use the same beamand the power ramping suspension instruction which is used to instructthe MAC layer by the physical layer is not received, adding one stepsize to the transmission power;

otherwise, keeping the transmission power unchanged.

The step size is configured by the base station for the terminal ordetermined according to a preset rule.

In this situation, the configuration situation of the beam preamblere-transmission counter includes:

when the random access preamble is transmitted on a first beam and theRAR message is not correctly received in preset time, adding one to abeam preamble retransmission counter configured based on the first beam;

when a random access message three is transmitted on a second beam andthe contention resolution fails, adding one to a beam preambleretransmission counter configured based on the second beam; or,

when the preamble is transmitted on the third beam, the random accessmessage three is transmitted on a fourth beam and the contentionresolution fails, adding one to a beam preamble retransmission counterconfigured based on the third beam, or respectively adding one to thebeam preamble retransmission counter configured based on the third beamand a beam preamble retransmission counter configured based on thefourth beam.

Further, when a count value of the beam preamble retransmission counterreaches a second preset maximum number of times of transmission Max2 orMax2+1, the method further includes:

when next retransmission of the random access preamble is performed inthis random access procedure, switching beams;

when the next retransmission of the random access preamble is performedin this random access procedure, removing a beam, which is used toperform previous transmission of the random access preamble fromcandidate beams for next retransmission of the random access preamble;or

notifying an upper layer of a random access problem or failure of therandom access procedure via the MAC layer.

Further, when count values of a first preset number of beam preambleretransmission counters reach a third preset maximum number of times oftransmission Max3 or Max3+1, an upper layer is notified of a randomaccess problem or failure of the random access procedure via the MAClayer; or

when a sum of count values of a second preset number of beam preambleretransmission counters reaches a third preset maximum number of timesof transmission Max3 or Max3+1, the upper layer is notified of therandom access problem or the failure of the random access procedure viathe MAC layer.

In this situation, the configuration situation of the power rampingcounter includes:

when any of not correctly receiving the RAR message in the preset time,contention resolution failure and retransmission of the preamble occursand two adjacent transmissions of the preamble use the same beam, addingone to the power ramping counter; or

when any of not correctly receiving the RAR message in the preset time,contention resolution failure and retransmission of the preamble occurs,two adjacent transmissions of the preamble use the same beam and thepower ramping suspension instruction which is used to instruct the MAClayer by the physical layer is not received, adding one to the powerramping counter.

Further, when the power ramping counter is configured based on a singlebeam and when the beams are switched at each re-transmission, the valueof the power ramping counter corresponding to the current beam is resetto that of the power ramping counter corresponding to a transmissionbeam, which is used to perform the previous transmission of the randomaccess preamble.

Therefore, in this situation, when the terminal has the power rampingcounter and when the ramping power is determined, following modes arepreferred:

obtaining a transmission power of retransmission after ramping accordingto a formulaPREAMBLE_RECEIVED_TARGET_POWER=preambleInitialReceivedTargetPower+DELTA_PREAMBLE+(POWER_RAMPING_COUNTER−1)* powerRampingStep;

where PREAMBLE_RECEIVED_TARGET_POWER denotes a target power value,preambleInitialReceivedTargetPower denotes an original power value,DELTA_PREAMBLE denotes a preset fixed value, POWER_RAMPING_COUNTERdenotes a value of the current power ramping counter andpowerRampingStep denotes a power ramping step size;

the power ramping step size is configured by the base station for theterminal or determined by a preset rule.

In this mode, when the transmission power is larger than or equals themaximum power, the method further includes:

transmitting, by the terminal, the random access preamble according tothe maximum power.

As for the above implementation situations, each implementationsituation may further include: a preamble retransmission beam switchingcounter or a power level preamble transmission counter.

Specifically, the usage mode and count rule of the preambleretransmission beam switching counter or power level preambletransmission counter have been described above, and will not be repeatedhere.

It should be noted that when the above counters are used in combination,each counter can realize its own independent functions, and when thereis a power ramping counter in the terminal and the ramping power isdetermined, the mode for obtaining the ramping power according to thepower ramping counter is preferred, that is, the transmission power ofthe retransmission after ramping is obtained via a formula:PREAMBLE_RECEIVED_TARGET_POWER=preambleInitialReceivedTargetPower+DELTA_PREAMBLE+(POWER_RAMPING_COUNTER−1)*powerRampingStep.

In embodiments of the present disclosure, in the random accessprocedure, when detecting that the RAR message is not correctly receivedor contention resolution fails, the number of times of retransmission ofthe preamble and/or the number of times of power ramping of thetransmission of the preamble are counted according to a configuredcounter/counters. Therefore, the problem of being unable tosimultaneously satisfy the functions of counting the power ramping andpreamble transmission when a single counter is used for counting boththe power ramping and preamble transmission, can be avoided. With themode in the embodiments of the present disclosure, the reliability ofcommunication of the NR system can be guaranteed.

As shown in FIG. 2, the terminal in embodiments of the presentdisclosure includes:

a processing module configured to, in a random access procedure, whendetecting that no Random Access Response (RAR) is received or contentionresolution fails, count a number of times of preamble retransmissionand/or a number of times of power ramping of preamble transmissionaccording to a configured counter/counters.

Optionally, the configured counter/counters includes: one type ofcounter;

when the RAR message is not correctly received or the contentionresolution fails, the counter adds 1; or

when the RAR message is not correctly received or the contentionresolution fails and a power ramping suspension instruction which isused to instruct a Medium Access Control (MAC) layer by a physical layeris not received, the counter adds 1.

Specifically, the counter/counters includes: a preamble transmissioncounter.

Specifically, when a count value of the preamble transmission counterreaches a first preset maximum number of times of transmission Max1 orMax1+1, an upper layer is notified of a random access problem or failureof the random access procedure via the MAC layer.

Specifically, when the preamble transmission counter counts preambleretransmission,

when two adjacent transmissions of the preamble use a same beam, thetransmission power adds one step size; or

when the two adjacent transmissions of the preamble use the same beamand the power ramping suspension instruction which is used to instructthe MAC layer by the physical layer is not received, the transmissionpower adds one step size;

otherwise, the transmission power is kept unchanged.

The step size is configured by the base station for the terminal ordetermined according to a preset rule.

Further, when an obtained transmission power is larger than or equalsthe maximum transmission power, the processing module is configured to:

transmit the random access preamble according to the maximum power.

Specifically, the counter includes: a beam preamble retransmissioncounter.

Specifically, when the preamble is transmitted on a first beam and theRAR message is not correctly received in preset time, a beam preambleretransmission counter configured based on the first beam adds 1;

when a random access message three is transmitted on a second beam andthe contention resolution fails, a beam preamble retransmission counterconfigured based on the second beam adds 1; or

when the preamble is transmitted on the third beam, the random accessmessage three is transmitted on a fourth beam and the contentionresolution fails, a beam preamble retransmission counter configuredbased on the third beam adds 1, or the beam preamble retransmissioncounter configured based on the third beam and a beam preambleretransmission counter configured based on the fourth beam respectivelyadd 1.

Specifically, when a count value of the beam preamble retransmissioncounter reaches a second preset maximum number of times of transmissionMax2 or Max2+1, the processing module is configured to:

when next retransmission of the random access preamble is performed inthis random access procedure, switch beams;

when the next retransmission of the random access preamble is performedin this random access procedure, remove a beam, which is used to performprevious transmission of the random access preamble from candidate beamsfor the next retransmission of the random access preamble; or

notify an upper layer of a random access problem or failure of therandom access procedure via the MAC layer.

Specifically, when the next retransmission of the random access preambleis performed in this random access procedure, the implementation mode ofremoving the beam, which is used to perform the previous transmission ofthe random access preamble from the candidate beams for the nextretransmission of the random access preamble, includes:

in preset time or a preset number of times, removing the beam, which isused to perform the previous transmission of the random access preamblefrom the candidate beams for the next retransmission of the randomaccess preamble.

Specifically, when reaching the preset time or preset number of times,the beam preamble retransmission counter is restarted.

Specifically, when the next retransmission of the random access preambleis performed in this random access procedure, the implementation mode ofremoving the beam, which is used to perform the previous transmission ofthe random access preamble from the candidate beams for the nextretransmission of the random access preamble, includes:

when transmission powers of the terminal are in a same power level orpreset number of power levels, removing the beam, which is used toperform the previous transmission of the random access preamble from thecandidate beams for the next retransmission of the random accesspreamble.

Specifically, when the transmission powers of the terminal exceed thesame power level or the preset number of power levels, the beam preambleretransmission counter is restarted.

Specifically, when count values of a first preset number of beampreamble retransmission counters reach a third preset maximum number oftimes of transmission Max3 or Max3+1, an upper layer is notified of arandom access problem or failure of the random access procedure via theMAC layer.

Specifically, when a sum of count values of a second preset number ofbeam preamble retransmission counters reaches a third preset maximumnumber of times of transmission Max3 or Max3+1, an upper layer isnotified of a random access problem or failure of the random accessprocedure via the MAC layer.

Specifically, the method for counting preamble retransmission in therandom access procedure further includes:

when two adjacent transmissions of the preamble use a same beam, addingone step size to a transmission power; or

when the two adjacent transmissions of the preamble use the same beamand the power ramping suspension instruction which is used to instructthe MAC layer by the physical layer is not received, adding one stepsize to the transmission power;

otherwise, keeping the transmission power unchanged.

The step size is configured by the base station for the terminal ordetermined according to a preset rule.

Specifically, when an obtained transmission power is larger than orequals the maximum transmission power, the processing module isconfigured to:

transmit the random access preamble according to the maximum power.

Specifically, the counter/counters includes a power ramping counter.

Specifically, when any of not correctly receiving the RAR message inpreset time, contention resolution failure and retransmission of thepreamble occurs and two adjacent transmissions of the preamble use asame beam, the power ramping counter adds 1; or

when any of not correctly receiving the RAR message in the preset time,contention resolution failure and retransmission of the preamble occurs,two adjacent transmissions of the preamble use the same beam and thepower ramping suspension instruction which is used to instruct the MAClayer by the physical layer is not received, the power ramping counteradds 1.

Specifically, when the power ramping counter is configured based on asingle beam and the beams are switched at each retransmission, the valueof the power ramping counter corresponding to the current beam is resetto that of the power ramping counter corresponding to a transmissionbeam, which is used to perform the previous transmission of the randomaccess preamble.

Specifically, the transmission power of retransmission after ramping isobtained according to a formulaPREAMBLE_RECEIVED_TARGET_POWER=preambleInitialReceivedTargetPower+DELTA_PREAMBLE+(POWER_RAMPING_COUNTER−1)* powerRampingStep;

where PREAMBLE_RECEIVED_TARGET_POWER denotes a target power value,preambleInitialReceivedTargetPower denotes an original power value,DELTA_PREAMBLE denotes a preset fixed value, POWER_RAMPING_COUNTERdenotes a value of the current power ramping counter andpowerRampingStep denotes a power ramping step size;

the power ramping step size is configured by the base station for theterminal or determined by a preset rule.

Further, when a transmission power obtained via calculation is largerthan or equals the maximum power, the processing module is furtherconfigured to:

transmit the random access preamble according to the maximum power.

Specifically, the method for counting preamble retransmission in therandom access procedure further includes:

when a count value of the power ramping counter reaches a maximum numberof times or the maximum number of times plus 1 and when not correctlyreceiving the RAR messages or contention resolution failure occurs for apreset number of times in the present time, an upper layer is notifiedof a random access problem or failure of the random access procedure viathe MAC layer.

Specifically, the counter/counters includes: a preamble retransmissionbeam switching counter or a power level preamble transmission counter.

Specifically, when beams are switched when the preamble isre-transmitted, the preamble retransmission beam switching counter orpower level preamble transmission counter adds 1.

Specifically, when the preamble retransmission beam switching counter orpower level preamble transmission counter reaches a preset maximumnumber of times Max4 or Max4+1, the processing module is configured to:

perform power ramping when re-transmitting the random access preambleand reset the preamble retransmission beam switching counter or powerlevel preamble transmission counter;

at next retransmission of the random access preamble, keeping beamsun-switched; or

at the next retransmission of the random access preamble, switch to abeam, which has not been used to transmit the random access preamble, tore-transmit the random access preamble.

Specifically, an implementation mode of switching to the beam, which hasnot been used to transmit the random access preamble, to re-transmit therandom access preamble includes:

switching to a beam that is in a same power level or preset number ofpower levels with the current beam and has not been used to transmit therandom access preamble, to re-transmit the random access preamble.

Specifically, when a transmission power used by the terminal fortransmitting the preamble changes, the preamble retransmission beamswitching counter or power level preamble transmission counter is reset.

Specifically, when the preamble retransmission beam switching counter orpower level preamble transmission counter reaches the maximum countvalue and a current transmission power of a terminal reaches the maximumtransmission power, the upper layer is notified of a random accessproblem or failure of the random access procedure via the MAC layer.

Optionally, the configured counters include: at least two types ofcounters;

when the counters reach the maximum count value, the upper layer isnotified of a random access problem or failure of the random accessprocedure via the MAC layer.

Specifically, the at least two types of counters include: a preambletransmission counter and a beam preamble retransmission counter.

Specifically, when the preamble is transmitted on a first beam and noRAR message is received in preset time, a beam preamble retransmissioncounter configured based on the first beam adds 1;

when a random access message three is transmitted on a second beam andthe contention resolution fails, a beam preamble retransmission counterconfigured based on the second beam adds 1; or

when the preamble is transmitted on a third beam, a random accessmessage three is transmitted on a fourth beam and the contentionresolution fails, a beam preamble retransmission counter configuredbased on the third beam adds 1, or the beam preamble retransmissioncounter configured based on the third beam and a beam preambleretransmission counter configured based on the fourth beam respectivelyadd 1.

Specifically, when a count value of the beam preamble retransmissioncounter reaches a second preset maximum number of times of transmissionMax2 or Max2+1, the processing module is further configured to:

when next retransmission of the random access preamble is performed inthis random access procedure, switch beams;

when the next retransmission of the random access preamble is performedin this random access procedure, remove a beam, which is used to performprevious transmission of the random access preamble from candidate beamsfor the next retransmission of the random access preamble; or

notify an upper layer of a random access problem or failure of therandom access procedure via the MAC layer.

Specifically, when two adjacent transmissions of the preamble use a samebeam, a transmission power adds one step size; or

when the two adjacent transmissions of the preamble use the same beamand the power ramping suspension instruction which is used to instructthe MAC layer by the physical layer is not received, the transmissionpower adds one step size;

otherwise, the transmission power is kept unchanged;

where the step size is configured by the base station for the terminalor determined according to a preset rule.

Specifically, when an obtained transmission power is larger than orequals the maximum transmission power, the processing module is furtherconfigured to:

transmit the random access preamble according to the maximum power.

Specifically, the method for counting preamble retransmission in therandom access procedure further includes :

when a count value of the preamble transmission counter reaches a firstpreset maximum number of times of transmission Max1 or Max1+1, notifyingan upper layer of a random access problem or failure of the randomaccess procedure via the MAC layer;

when count values of a first preset number of beam preambleretransmission counters reach a third preset maximum number of times oftransmission Max3 or Max3+1, notifying the upper layer of the randomaccess problem or the failure of the random access procedure via the MAClayer; or

when a sum of count values of a second preset number of beam preambleretransmission counters reaches the third preset maximum number of timesof transmission Max3 or Max3+1, notifying the upper layer of the randomaccess problem or the failure of the random access procedure via the MAClayer.

Specifically, the at least two types of counters include: a preambletransmission counter and a power ramping counter.

Specifically, when the RAR message is not correctly received by thepreamble transmission counter in preset time or the contentionresolution fails, the preamble transmission counter adds 1.

Specifically, when a count value of the preamble transmission counterreaches a first preset maximum number of times of transmission Max1 orMax1+1, the upper layer is notified of a random access problem orfailure of the random access procedure via the MAC layer.

Specifically, when the preamble transmission counter counts preambleretransmission,

when and two adjacent transmissions of the preamble use a same beam, atransmission power adds one step size; or

when the two adjacent transmissions of the preamble use the same beamand the power ramping suspension instruction which is used to instructthe MAC layer by the physical layer is not received, the transmissionpower adds one step size;

otherwise, the transmission power is kept unchanged;

where the step size is configured by the base station for the terminalor determined according to a preset rule.

Specifically, when any of not correctly receiving the RAR message inpreset time, contention resolution failure and retransmission of thepreamble occurs and two adjacent transmissions of the preamble use asame beam, the power ramping counter adds 1; or

when any of not correctly receiving the RAR message in the preset time,contention resolution failure and retransmission of the preamble occurs,two adjacent transmissions of the preamble use the same beam and thepower ramping suspension instruction which is used to instruct the MAClayer by the physical layer is not received, the power ramping counteradds 1.

Specifically, when the power ramping counter is configured based on asingle beam and the beams are switched at each retransmission, the valueof the power ramping counter corresponding to the current beam is resetto that of the power ramping counter corresponding to a transmissionbeam, which is used to perform the previous transmission of the randomaccess preamble.

Specifically, the transmission power of retransmission after ramping isobtained according to a formulaPREAMBLE_RECEIVED_TARGET_POWER=preambleInitialReceivedTargetPower+DELTA_PREAMBLE+(POWER_RAMPIN_COUNTER−1)*powerRampingStep

where PREAMBLE_RECEIVED_TARGET_POWER denotes a target power value,preambleInitialReceivedTargetPower denotes an original power value,DELTA_PREAMBLE denotes a preset fixed value, POWER_RAMPING_COUNTERdenotes a value of the current power ramping counter andpowerRampingStep denotes a power ramping step size;

the power ramping step size is configured by the base station for theterminal or determined by a preset rule.

Specifically, when a transmission power obtained via calculation islarger than or equals the maximum power, the processing module isfurther configured to transmit the random access preamble according tothe maximum power.

Specifically, the at least two types of counters include: a beampreamble retransmission counter and a power ramping counter.

Specifically, the transmission power of retransmission after ramping isobtained according to a formulaPREAMBLE_RECEIVED_TARGET_POWER=preambleInitialReceivedTargetPower+DELTA_PREAMBLE+(POWER_RAMPING_COUNTER−1)* powerRampingStep;

where PREAMBLE_RECEIVED_TARGET_POWER denotes a target power value,preambleInitialReceivedTargetPower denotes an original power value,DELTA_PREAMBLE denotes a preset fixed value, POWER_RAMPING_COUNTERdenotes a value of the current power ramping counter andpowerRampingStep denotes a power ramping step size;

the power ramping step size is configured by the base station for theterminal or determined by a preset rule.

Specifically, when any of not correctly receiving the RAR message in thepreset time, contention resolution failure and retransmission of thepreamble occurs and two adjacent transmissions of the preamble use thesame beam, the power ramping counter adds 1; or

when any of not correctly receiving the RAR message in the preset time,contention resolution failure and retransmission of the preamble occurs,two adjacent transmissions of the preamble use the same beam and thepower ramping suspension instruction which is used to instruct the MAClayer by the physical layer is not received, the power ramping counteradds 1.

Specifically, when the power ramping counter is configured based on asingle beam and the beams are switched at each retransmission, the valueof the power ramping counter corresponding to the current beam is resetto that of the power ramping counter corresponding to a transmissionbeam, which is used to perform the previous transmission of the randomaccess preamble.

Specifically, when the preamble is transmitted on a first beam and theRAR message is not received in preset time, a beam preambleretransmission counter configured based on the first beam adds 1;

when a random access message three is transmitted on a second beam andthe contention resolution fails, a beam preamble retransmission counterconfigured based on the second beam adds 1; or

when the preamble is transmitted on the third beam, the random accessmessage three is transmitted on a fourth beam and the contentionresolution fails, a beam preamble retransmission counter configuredbased on the third beam adds 1, or the beam preamble retransmissioncounter configured based on the third beam and a beam preambleretransmission counter configured based on the fourth beam respectivelyadds 1.

Specifically, when a count value of the beam preamble retransmissioncounter reaches a second preset maximum number of times of transmissionMax2 or Max2+1, the processing module is further configured to:

when next retransmission of the random access preamble is performed inthis random access procedure, switch beams;

when the next retransmission of the random access preamble is performedin this random access procedure, remove a beam, which is used to performprevious transmission of the random access preamble from candidate beamsfor next retransmission of the random access preamble; or

notify an upper layer of a random access problem or failure of therandom access procedure via the MAC layer.

Specifically, when count values of a first preset number of beampreamble retransmission counters reach a third preset maximum number oftimes of transmission Max3 or Max3+1, an upper layer is notified of arandom access problem or failure of the random access procedure via theMAC layer; or

when a sum of count values of a second preset number of beam preambleretransmission counters reach a third preset maximum number of times oftransmission Max3 or Max3+1, the upper layer is notified of the randomaccess problem or the failure of the random access procedure via the MAClayer.

Specifically, the at least two types of counters include: a preambletransmission counter, a beam preamble retransmission counter and a powerramping counter.

Specifically, when the RAR message is not correctly received in presettime or the contention resolution fails, the preamble transmissioncounter adds 1.

Specifically, when a count value of the preamble transmission counterreaches a first preset maximum number of times of transmission Max1 orMax1+1, an upper layer is notified of a random access problem or failureof the random access procedure via the MAC layer.

Specifically, when the preamble transmission counter counts preambleretransmission,

when two adjacent transmissions of the preamble use a same beam, atransmission power adds one step size; or

when the two adjacent transmissions of the preamble use the same beamand the power ramping suspension instruction which is used to instructthe MAC layer by the physical layer is not received, the transmissionpower adds one step size;

otherwise, the transmission power is kept unchanged;

where the step size is configured by the base station for the terminalor determined according to a preset rule.

Specifically, when the preamble is transmitted on a first beam and theRAR message is not correctly received in preset time, a beam preambleretransmission counter configured based on the first beam adds 1;

when a random access message three is transmitted on a second beam andthe contention resolution fails, a beam preamble retransmission counterconfigured based on the second beam adds 1; or

when the preamble is transmitted on a third beam, the random accessmessage three is transmitted on a fourth beam and the contentionresolution fails, a beam preamble retransmission counter configuredbased on the third beam adds 1, or the beam preamble retransmissioncounter configured based on the third beam and a beam preamblere-transmission counter configured based on the fourth beam respectivelyadd 1.

Specifically, when a count value of the beam preamble retransmissioncounter reaches s second preset maximum number of times of transmissionMax2 or Max2+1, the processing module is further configured to:

when next retransmission of the random access preamble is performed inthis random access procedure, switch beams;

when the next retransmission of the random access preamble is performedin this random access procedure, remove a beam, which is used to performprevious transmission of the random access preamble from candidate beamsfor next retransmission of the random access preamble; or

notify an upper layer of a random access problem or failure of therandom access procedure via the MAC layer.

Specifically, when count values of a first preset number of beampreamble retransmission counters reach a third preset maximum number oftimes of transmission Max3 or Max3+1, the upper layer is notified of therandom access problem or failure of the random access procedure via theMAC layer; or

when a sum of count values of a second preset number of beam preambleretransmission counters reaches a third preset maximum number of timesof transmission Max3 or Max3+1, the upper layer is notified of therandom access problem or the failure of the random access procedure viathe MAC layer.

Specifically, when any of not correctly receiving the RAR message in thepreset time, contention resolution failure and retransmission of thepreamble occurs and two adjacent transmissions of the preamble use thesame beam, the power ramping counter adds 1; or

when any of not correctly receiving the RAR message in the preset time,contention resolution failure and retransmission of the preamble occurs,two adjacent transmissions of the preamble use the same beam and thepower ramping suspension instruction which is used to instruct the MAClayer by the physical layer is not received, the power ramping counteradds 1.

Specifically, when the power ramping counter is configured based on asingle beam and the beams are switched at each retransmission, the valueof the power ramping counter corresponding to the current beam is resetto that of the power ramping counter corresponding to a transmissionbeam, which is used to perform the previous transmission of the randomaccess preamble.

Specifically, the transmission power of retransmission after ramping isobtained according to a formula

PREAMBLE_RECEIVED_TARGET_POWER=preambleInitialReceivedTargetPower+DELTA_PREAMBLE+(POWER_RAMPING_COUNTER−1)* powerRampingStep;

where PREAMBLE_RECEIVED_TARGET_POWER denotes a target power value,preambleInitialReceivedTargetPower denotes an original power value,DELTA_PREAMBLE denotes a preset fixed value, POWER_RAMPING_COUNTERdenotes a value of the current power ramping counter andpowerRampingStep denotes a power ramping step size;

the power ramping step size is configured by the base station for theterminal or determined by a preset rule.

Further, when the transmission power is larger than or equals themaximum power, the processing module is further configured to:

transmit the random access preamble according to the maximum power.

Specifically, the at least two types of counters include: a preambleretransmission beam switching counter or a power level preambletransmission counter.

Specifically, when beams are switched when the preamble isre-transmitted, the preamble retransmission beam switching counter orpower level preamble transmission counter adds 1.

Specifically, when the preamble retransmission beam switching counter orpower level preamble transmission counter reaches a preset maximumnumber of times Max4 or Max4+1, the processing module is furtherconfigured to:

perform power ramping when re-transmitting the random access preambleand reset the preamble retransmission beam switching counter or powerlevel preamble transmission counter;

at next retransmission of the random access preamble, keep beamsun-switched; or

at the next retransmission of the random access preamble, switch to abeam, which has not been used to transmit the random access preamble, tore-transmit the random access preamble.

Specifically, an implementation mode of switching to the beam, which hasnot been used to transmit the random access preamble, to re-transmit therandom access preamble, includes:

switching to a beam that is in a same power level or preset number ofpower levels with the current beam and has not been used to transmit therandom access preamble, to re-transmit the random access preamble.

Specifically, when the preamble retransmission beam switching counter orpower level preamble transmission counter reaches the maximum countvalue and a current transmission power of a terminal reaches the maximumtransmission power, the upper layer is notified of the random accessproblem or failure of the random access procedure via the MAC layer.

Specifically, when a transmission power used by the terminal fortransmitting the preamble changes, the preamble retransmission beamswitching counter or power level preamble transmission counter is reset.

It should be noted that the terminal embodiment is that corresponding tothe method for counting preamble retransmission in the random accessprocedure applied to the terminal side. All implementation modes in theabove embodiments are applicable to this terminal embodiment andtechnical effects of all implementation modes in this terminalembodiment are the same as those of the implementation modes in theabove embodiments.

Embodiments of the present disclosure further provide a terminal,including: a storage, a processor and computer programs, which arestored in the storage and run on the processor. When the computerprograms are executed by the processor, each process in the methodembodiment for counting preamble retransmission in a random accessprocedure at the terminal side is implemented and the same technicaleffects may be achieved. In order to avoid repetition, the method is notrepeated here.

Embodiments of the present disclosure further provide a computerreadable storage medium, storing computer programs. When the computerprograms are executed by a processor, each process in the methodembodiment for counting preamble retransmission in a random accessprocedure at the terminal side is implemented and the same technicaleffects may be achieved. In order to avoid repetition, the method is notrepeated here. The aforesaid computer readable storage medium includes aread-only Memory (ROM), Random Access Memory (RAM), a disk or disc, etc.

As shown in FIG. 3, FIG. 3 is a diagram illustrating structure of aterminal of an embodiment of the present disclosure. The applicationentity of the method for counting preamble retransmission in a randomaccess procedure of the present disclosure is described hereinafter indetail accompanying with the figure.

The terminal 300 shown in FIG. 3 includes: at least one first processor301, a storage 302, at least one network interface 304 and a userinterface 303. Each component in the terminal 300 is coupled togethervia bus system 305. It can be understood that the bus system 305 is usedto implement connected communication among these components. Besides adata bus, the bus system 305 further includes: a power bus, control busand a state signal bus. For clear description, various buse in FIG. 3are denoted as the bus system 305.

The user interface 303 may include a monitor, keyboard, or clickabledevice (for example, a mouse, track ball, touchpad, or touch screen).

It can be understood that the storage 302 in embodiments of the presentdisclosure can be a volatile storage or a nonvolatile storage, or boththe volatile storage and non-volatile storage. The nonvolatile storagecan be Read Only Memory (ROM), Programmable Read-Only Memory (PROM),Erasable Programmable Read-Only Memory (EPROM), Electrically ErasableProgrammable Read-Only Memory (EEPROM) or flash. The volatile storagecan be Random Access Memory (RAM), which is used as an external cache.As an illustrative but not restrictive specification, many forms of RAMsare available, such as Static RAM (SRAM), Dynamic RAM (DRAM),Synchronous DRAM (SDRAM), Double Data Rate SDRAM (DDRSDRAM), EnhancedSDRAM (ESDRAM), Synchronization Link DRAM (SLDRAM) and Direct Rambus RAM(DRRAM). The storage 302 in the system and method described inembodiments of the present disclosure include, but is not limited to,these and any other suitable types of storages.

In some embodiments, the storage 302 stores following elements, such asexecutable modules, data structure, subset thereof, or superset thereof:operating system (OS) 3021 and application programs 3022.

The OS 3021 includes various kinds of system programs, such as aframework layer, a core library layer and a driver layer, which are usedto implement various kinds of basic services and process hardware-basedtasks. The application programs 3022 include various kinds ofapplication programs, such as Media Player and Browser, which are usedto implement various kinds of application services. Programs, which areused to implement the methods in embodiments of the present disclosure,may be included in the application programs 3022.

In an embodiment of the present disclosure, the terminal 300 furtherincludes: the computer programs, which are stored in the storage 302 andmay run on the processor 301. Specifically, the computer programs may becomputer control programs in the application programs 3022. When thecomputer programs are executed by the processor 301, following steps areimplemented: in a random access procedure, when detecting that no RandomAccess Response (RAR) is received or contention resolution fails,counting a number of times of retransmission of the preamble and/or anumber of times of power ramping of the transmission of the preambleaccording to a configured counter/counters.

The methods in the above embodiments of the present disclosure may beapplied to or implemented by the processor 301. The processor 301 may bean integrated circuit chip with signal processing power. In theimplementation process, each step of the above method can be completedby the integrated logic circuit of the hardware in processor 301 or theinstructions in the form of software. The processor 301 mentioned abovemay be a general purpose Processor, Digital Signal Processor (DSP),Application Specific Integrated Circuit (ASIC), Field Programmable GateArray (FPGA) or other Programmable logic device, discrete Gate ortransistor logic device, discrete hardware component. Methods, steps andlogical block diagrams disclosed in this public embodiment may berealized or implemented. A general-purpose processor can be amicroprocessor or the general-purpose processor can be any regularprocessor, etc. The steps in combination with the method disclosed inthis public embodiment may be directly embodied as the execution of thehardware decoding processor or by a combination of hardware and softwaremodules in the decoding processor. Software modules can be located inrandom access memory, flash memory, read only memory, programmable readonly memory or electrically-erasable programmable memory, register andother mature computer readable storage media in this field. The readablestorage medium of the computer is located in storage 302, and theprocessor 301 reads the information in the storage 302 to implementsteps in the above method in combination with the hardware.Specifically, the computer programs are stored on the computer readablestorage medium. When the computer programs are executed by the processor301, following steps are executed.

It can be understood that these embodiments described in the presentdisclosure may be implemented with hardware, software, firmware,middleware, microcode, or a combination thereof. As for hardwareimplementation, the processing unit can be implemented in one ormultiple Application-Specific Integrated Circuits (ASIC), Digital SignalProcessors (DSP), Digital Signal Processing Devices (DSPD), ProgrammableLogic Devices (PLD), Field-Programmable Gate Arrays (FPGA),general-purpose processors, controllers, micro-controllers,micro-processors, and other electronic units or combinations thereofused to perform the functions described in this the present disclosure.

For software implementations, the technologies described in the presentdisclosure can be implemented through the modules that perform thefunctions described in the present disclosure (such as procedures,functions, and so on). Software codes can be stored in the storage andexecuted by the processor. The storage can be implemented in or outsideof the processor.

Optionally, the configured counter includes one type of counter and whenthe computer programs are executed by the processor 301, followingprocessing is implemented: when the RAR message is not correctlyreceived or the contention resolution fails, adding 1 to the counter; or

when the RAR message is not correctly received or the contentionresolution fails and a power ramping suspension instruction which isused to instruct a Medium Access Control (MAC) layer by a physical layeris not received, adding 1 to the counter.

Optionally, the counter includes: a preamble transmission counter, andwhen the computer programs are executed by the processor 301, followingprocessing is implemented: when a count value of the preambletransmission counter reaches a first preset maximum number of times oftransmission Max1 or Max1+1, notifying an upper layer of a random accessproblem or failure of the random access procedure via the MAC layer.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when the preamble transmissioncounter counts preamble re-transmission times,

when two adjacent transmissions of the preamble use a same beam, addingone step size to a transmission power; or

when the two adjacent transmissions of the preamble use the same beamand the power ramping suspension instruction which is used to instructthe MAC layer by the physical layer is not received, adding one stepsize to the transmission power;

otherwise, keeping the transmission power unchanged;

where the step size is configured by the base station for the terminalor determined according to a preset rule.

Optionally, when an obtained transmission power is larger than or equalsthe maximum transmission power and the computer programs are executed bythe processor 301, following processing is implemented:

transmitting the random access preamble according to the maximumtransmission power.

Optionally, the counter includes: a beam preamble retransmissioncounter. When the computer programs are executed by the processor 301,following processing is implemented: when the random access preamble istransmitted on a first beam and the RAR message is not received inpreset time, adding 1 to a beam preamble retransmission counterconfigured based on the first beam;

when a random access message three is transmitted on a second beam andthe contention resolution fails, adding 1 to a beam preambleretransmission counter configured based on the second beam; or

when the random access preamble is transmitted on the third beam, therandom access message three is transmitted on a fourth beam and thecontention resolution fails, adding 1 to a beam preamble retransmissioncounter configured based on the third beam, or respectively adding 1 tothe beam preamble retransmission counter configured based on the thirdbeam and a beam preamble retransmission counter configured based on thefourth beam.

Optionally, when a count value of the beam preamble retransmissioncounter reaches a second preset maximum number of times of transmissionMax2 or Max2+1 and the computer programs are executed by the processor301, following processing is implemented:

when next retransmission of the random access preamble is performed inthis random access procedure, switching beams;

when the next retransmission of the random access preamble is performedin this random access procedure, removing a beam, which is used toperform previous transmission of the random access preamble fromcandidate beams for next retransmission of the random access preamble;or

notifying an upper layer of a random access problem or failure of therandom access procedure via the MAC layer.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when the next retransmissionof the random access preamble is performed in this random accessprocedure, the implementation mode of removing the beam, which is usedto perform the previous transmission of the random access preamble fromthe candidate beams for the next retransmission of the random accesspreamble includes:

in preset time or preset number of times, removing the beam, which isused to perform the previous transmission of the random access preamblefrom the candidate beams for the next retransmission of the randomaccess preamble.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when reaching the preset timeor preset number of times, restarting the beam preamble retransmissioncounter.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when the next retransmissionof the random access preamble is performed in this random accessprocedure, the implementation mode for removing the beam, which is usedto perform the previous transmission of the random access preamble fromthe candidate beams for the next retransmission of the random accesspreamble includes:

when transmission powers of the terminal are in a same power level orpreset number of power levels, removing the beam, which is used toperform the previous transmission of the random access preamble from thecandidate beams for the next retransmission of the random accesspreamble.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when the transmission powersof the terminal exceed the same power level or the preset number ofpower levels, restarting the beam preamble re-transmission counter.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when count values of a firstpreset number of beam preamble retransmission counters reach a thirdpreset maximum number of times of transmission Max3 or Max3+1, notifyingan upper layer of a random access problem or failure of the randomaccess procedure via the MAC layer.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when a sum of count values ofa second preset number of beam preamble retransmission counters reachesa third preset maximum number of times of transmission Max3 or Max3+1,notifying an upper layer of a random access problem or failure of therandom access procedure via the MAC layer.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when two adjacenttransmissions of the preamble use a same beam, adding one step size to atransmission power; or

when the two adjacent transmissions of the preamble use the same beamand the power ramping suspension instruction which is used to instructthe MAC layer by the physical layer is not received, adding one stepsize to the transmission power;

otherwise, keeping the transmission power unchanged;

where the step size is configured by the base station for the terminalor determined according to a preset rule.

Optionally, when an obtained transmission power is larger than or equalsthe maximum transmission power and the computer programs are executed bythe processor 301, following processing is implemented: transmitting, bythe terminal, the random access preamble according to the maximum power,and/or instructing suspending power ramping.

Optionally, the counter includes a power ramping counter. When thecomputer programs are executed by the processor 301, followingprocessing is implemented: when any of not correctly receiving the RARmessage in preset time, contention resolution failure and retransmissionof the preamble occurs and two adjacent transmissions of the preambleuse a same beam, adding 1 to the power ramping counter; or

when any of not correctly receiving the RAR message in the preset time,contention resolution failure and retransmission of the preamble occurs,two adjacent transmissions of the preamble use the same beam and thepower ramping suspension instruction which is used to instruct the MAClayer by the physical layer is not received, adding 1 to the powerramping counter.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when the power ramping counteris configured based on a single beam and the beams are switched at eachretransmission, resetting the value of the power ramping countercorresponding to the current beam to that of the power ramping countercorresponding to a transmission beam, which is used to perform theprevious transmission of the random access preamble.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: obtaining a transmission powerof retransmission after ramping according to a formulaPREAMBLE_RECEIVED_TARGET_POWER=preambleInitialReceivedTargetPower+DELTA_PREAMBLE+(POWER_RAMPING_COUNTER−1)*powerRampingStep

where PREAMBLE_RECEIVED_TARGET_POWER denotes a target power value,preambleInitialReceivedTargetPower denotes an original power value,DELTA_PREAMBLE denotes a preset fixed value, POWER_RAMPING_COUNTERdenotes a value of the current power ramping counter andpowerRampingStep denotes a power ramping step size;

the power ramping step size is configured by the base station for theterminal or determined by a preset rule.

Optionally, when a transmission power obtained via calculation is largerthan or equals the maximum power and the computer programs are executedby the processor 301, following processing is implemented: transmittingthe random access preamble according to the maximum power.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when a count value of thepower ramping counter reaches the maximum number of times or the maximumnumber of times plus 1 and when not correctly receiving the RAR messagesor contention resolution failure occurs for a preset number of times inthe present time, notifying an upper layer of a random access problem orfailure of the random access procedure via the MAC layer.

Optionally, the counter includes: a preamble retransmission beamswitching counter or a power level preamble transmission counter. Whenthe computer programs are executed by the processor 301, followingprocessing is implemented: when beams are switched when the preamble isre-transmitted, adding 1 to the preamble retransmission beam switchingcounter or power level preamble transmission counter.

Optionally, when the preamble retransmission beam switching counter orpower level preamble transmission counter reaches a preset maximumnumber of times Max4 or Max4+1 and when the computer programs areexecuted by the processor 301, following processing is implemented:

performing power ramping when re-transmitting the random access preambleand resetting the preamble retransmission beam switching counter orpower level preamble transmission counter ;

at next retransmission of the random access preamble, keeping beamsun-switched; or

at the next retransmission of the random access preamble, switching to abeam, which has not been used to transmit the random access preamble, tore-transmit the random access preamble.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: an implementation mode ofswitching to the beam, which has not been used to transmit the randomaccess preamble, to re-transmit the random access preamble includes:

switching to a beam that is in a same power level or preset number ofpower levels with the current beam and has not been used to transmit therandom access preamble, to re-transmit the random access preamble.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when a transmission power usedby a terminal for transmitting the preamble changes, resetting thepreamble retransmission beam switching counter or power level preambletransmission counter.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when the preambleretransmission beam switching counter or power level preambletransmission counter reaches the maximum count value and a currenttransmission power of a terminal reaches the maximum transmission power,notifying an upper layer of a random access problem or failure of therandom access procedure via the MAC layer.

Optionally, the configured counters include: at least two types ofcounters. When the computer programs are executed by the processor 301,following processing is implemented: when the counters reach the maximumcounting quantities, notifying an upper layer of a random access problemor failure of the random access procedure via the MAC layer.

Optionally, the at least two types of counters include: a preambletransmission counter and a beam preamble retransmission counter. Whenthe computer programs are executed by the processor 301, followingprocessing is implemented: when the random access preamble istransmitted on a first beam and the RAR message is not received inpreset time, adding 1 to a beam preamble retransmission counterconfigured based on the first beam;

when a random access message three is transmitted on a second beam andthe contention resolution fails, adding 1 to a beam preambleretransmission counter configured based on the second beam; or

when the random access preamble is transmitted on a third beam, a randomaccess message three is transmitted on a fourth beam and the contentionresolution fails, adding 1 to a beam preamble retransmission counterconfigured based on the third beam, or respectively adding 1 to the beampreamble retransmission counter configured based on the third beam and abeam preamble retransmission counter configured based on the fourthbeam.

Optionally, when a count value of the beam preamble retransmissioncounter reaches a second preset maximum number of times of transmissionMax2 or Max2+1 and when the computer programs are executed by theprocessor 301, following processing is implemented: when nextretransmission of the random access preamble is performed in this randomaccess procedure, switching beams;

when the next retransmission of the random access preamble is performedin this random access procedure, removing a beam, which is used toperform previous transmission of the random access preamble fromcandidate beams for the next retransmission of the random accesspreamble; or

notifying an upper layer of a random access problem or failure of therandom access procedure via the MAC layer.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when two adjacenttransmissions of the preamble use a same beam, adding one step size to atransmission power; or

when the two adjacent transmissions of the preamble use the same beamand the power ramping suspension instruction which is used to instructthe MAC layer by the physical layer is not received, adding one stepsize to the transmission power;

otherwise, keeping the transmission power unchanged;

where the step size is configured by the base station for the terminalor determined according to a preset rule.

Optionally, when an obtained transmission power is larger than or equalsthe maximum transmission power and when the computer programs areexecuted by the processor 301, following processing is implemented:transmitting the random access preamble according to the maximum power.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when a count value of thepreamble transmission counter reaches a first preset maximum number oftimes of transmission Max1 or Max1+1, notifying an upper layer of arandom access problem or failure of the random access procedure via theMAC layer;

when count values of a first preset number of beam preambleretransmission counters reach a third preset maximum number of times oftransmission Max3 or Max3+1, notifying the upper layer of the randomaccess problem or the failure of the random access procedure via the MAClayer; or

when a sum of count values of a second preset number of beam preambleretransmission counters reaches a third preset maximum number of timesof transmission Max3 or Max3+1, notifying the upper layer of the randomaccess problem or the failure of the random access procedure via the MAClayer.

Optionally, the at least two types of counters include: a preambletransmission counter and a power ramping counter. When the computerprograms are executed by the processor 301, following processing isimplemented: when the RAR message is not correctly received in presettime or the contention resolution fails, adding 1 to the preambletransmission counter.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when a count value of thepreamble transmission counter reaches a first preset maximum number oftimes of transmission Max1 or Max1+1, notifying an upper layer of arandom access problem or failure of the random access procedure via theMAC layer.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when the preamble transmissioncounter counts preamble retransmission,

when two adjacent transmissions of the preamble use a same beam, addingone step size to a transmission power; or

when the two adjacent transmissions of the preamble use the same beamand the power ramping suspension instruction which is used to instructthe MAC layer by the physical layer is not received, adding one stepsize to the transmission power;

otherwise, keeping the transmission power unchanged;

where the step size is configured by the base station for the terminalor determined according to a preset rule.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when any of not correctlyreceiving the RAR message in preset time, contention resolution failureand retransmission of the preamble occurs and two adjacent transmissionsof the preamble use a same beam, adding 1 to the power ramping counter;or

when any of not correctly receiving the RAR message in the preset time,contention resolution failure and retransmission of the preamble occurs,two adjacent transmissions of the preamble use the same beam and thepower ramping suspension instruction which is used to instruct the MAClayer by the physical layer is not received, adding 1 to the powerramping counter.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when the power ramping counteris configured based on a single beam and the beams are switched at eachretransmission, resetting the value of the power ramping countercorresponding to the current beam to that of the power ramping countercorresponding to a transmission beam, which is used to perform theprevious transmission of the random access preamble.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: obtaining a transmission powerof retransmission after ramping according to a formulaPREAMBLE_RECEIVED_TARGET_POWER=preambleInitialReceivedTargetPower+DELTA_PREAMBLE+(POWER_RAMPING_COUNTER−1)* powerRampingStep;

where PREAMBLE_RECEIVED_TARGET_POWER denotes a target power value,preambleInitialReceivedTargetPower denotes an original power value,DELTA_PREAMBLE denotes a preset fixed value, POWER_RAMPING_COUNTERdenotes a value of the current power ramping counter andpowerRampingStep denotes a power ramping step size;

the power ramping step size is configured by the base station for theterminal or determined by a preset rule.

Optionally, when a transmission power obtained via calculation is largerthan or equals the maximum power and when the computer programs areexecuted by the processor 301, following processing is implemented:transmitting the random access preamble according to the maximum power.

Optionally, the at least two types of counters include: a beam preambleretransmission counter and a power ramping counter. When the computerprograms are executed by the processor 301, following processing isimplemented: obtaining a transmission power of retransmission afterramping according to a formulaPREAMBLE_RECEIVED_TARGET_POWER=preambleInitialReceivedTargetPower+DELTA_PREAMBLE+(POWER_RAMPING_COUNTER−1)*powerRampingStep

where PREAMBLE_RECEIVED_TARGET_POWER denotes a target power value,preambleInitialReceivedTargetPower denotes an original power value,DELTA_PREAMBLE denotes a preset fixed value, POWER_RAMPING_COUNTERdenotes a value of the current power ramping counter andpowerRampingStep denotes a power ramping step size;

the power ramping step size is configured by the base station for theterminal or determined by a preset rule.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when any of not correctlyreceiving the RAR message in preset time, contention resolution failureand retransmission of the preamble occurs and two adjacent transmissionsof the preamble use a same beam, adding 1 to the power ramping counter;or

when any of not correctly receiving the RAR message in the preset time,contention resolution failure and retransmission of the preamble occurs,two adjacent transmissions of the preamble use the same beam and thepower ramping suspension instruction which is used to instruct the MAClayer by the physical layer is not received, adding 1 to the powerramping counter.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when the power ramping counteris configured based on a single beam and the beams are switched at eachretransmission, resetting the value of the power ramping countercorresponding to the current beam to that of the power ramping countercorresponding to a transmission beam, which is used to perform theprevious transmission of the random access preamble.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when the random accesspreamble is transmitted on a first beam and the RAR message is notreceived in preset time, adding 1 to a beam preamble retransmissioncounter configured based on the first beam;

when a random access message three is transmitted on a second beam andthe contention resolution fails, adding 1 to a beam preambleretransmission counter configured based on the second beam; or

when the random access preamble is transmitted on a third beam, therandom access message three is transmitted on a fourth beam and thecontention resolution fails, adding 1 to a beam preamble retransmissioncounter configured based on the third beam, or respectively adding 1 tothe beam preamble retransmission counter configured based on the thirdbeam and a beam preamble retransmission counter configured based on thefourth beam.

Optionally, when a count value of the beam preamble retransmissioncounter reaches a second preset maximum number of times of transmissionMax2 or Max2+1 and when the computer programs are executed by theprocessor 301, following processing is implemented:

when next retransmission of the random access preamble is performed inthis random access procedure, switching beams;

when the next retransmission of the random access preamble is performedin this random access procedure, removing a beam, which is used toperform previous transmission of the random access preamble fromcandidate beams for next retransmission of the random access preamble;or

notifying an upper layer of a random access problem or failure of therandom access procedure via the MAC layer.

Optionally, when the computer programs are executed by the processor301, following processing is implemented:

when count values of a first preset number of beam preambleretransmission counters reach a third preset maximum number of times oftransmission Max3 or Max3+1, notifying an upper layer of a random accessproblem or failure of the random access procedure via the MAC layer; or

when a sum of count values of a second preset number of beam preambleretransmission counters reaches the third preset maximum number of timesof transmission Max3 or Max3+1, notifying the upper layer of the randomaccess problem or the failure of the random access procedure via the MAClayer.

Optionally, the at least two types of counters include: a preambletransmission counter, a beam preamble retransmission counter and a powerramping counter. When the computer programs are executed by theprocessor 301, following processing is implemented: when the RAR messageis not correctly received in preset time or the contention resolutionfails, adding 1 to the preamble transmission counter.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when a count value of thepreamble transmission counter reaches a first preset maximum number oftimes of transmission Max1 or Max1+1, notifying an upper layer of arandom access problem or failure of the random access procedure via theMAC layer.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when the preamble transmissioncounter counts preamble retransmission and two adjacent transmissions ofthe preamble use a same beam, adding one step size to a transmissionpower; or

when the two adjacent transmissions of the preamble use the same beamand the power ramping suspension instruction which is used to instructthe MAC layer by the physical layer is not received, adding one stepsize to the transmission power;

otherwise, keeping the transmission power unchanged;

wherein the step size is configured by the base station for the terminalor determined according to a preset rule.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when the random accesspreamble is transmitted on a first beam and the RAR message is notcorrectly received in preset time, adding 1 to a beam preambleretransmission counter configured based on the first beam;

when a random access message three is transmitted on a second beam andthe contention resolution fails, adding 1 to a beam preambleretransmission counter configured based on the second beam; or

when the random access preamble is transmitted on the third beam, therandom access message three is transmitted on a fourth beam and thecontention resolution fails, adding 1 to a beam preamble retransmissioncounter configured based on the third beam, or respectively adding 1 tothe beam preamble retransmission counter configured based on the thirdbeam and a beam preamble retransmission counter configured based on thefourth beam.

Optionally, when a count value of the beam preamble retransmissioncounter reaches a second preset maximum number of times of transmissionMax2 or Max2+1 and when the computer programs are executed by theprocessor 301, following processing is implemented: when nextretransmission of the random access preamble is performed in this randomaccess procedure, switching beams;

when the next retransmission of the random access preamble is performedin this random access procedure, removing a beam, which is used toperform previous transmission of the random access preamble fromcandidate beams for next retransmission of the random access preamble;or

notifying an upper layer of a random access problem or failure of therandom access procedure via the MAC layer.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when count values of a firstpreset number of beam preamble retransmission counters reach a thirdpreset maximum transmission times Max3 or Max3+1, notifying an upperlayer of a random access problem or failure of the random accessprocedure via the MAC layer; or

when a sum of count values of a second preset number of beam preambleretransmission counters reaches the third preset maximum number of timesof transmission Max3 or Max3+1, notifying the upper layer of the randomaccess problem or the failure of the random access procedure via the MAClayer.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when any of not correctlyreceiving the RAR message in the preset time, contention resolutionfailure and retransmission of the preamble occurs and two adjacenttransmissions of the preamble use the same beam, adding 1 to the powerramping counter; or

when any of not correctly receiving the RAR message in the preset time,contention resolution failure and retransmission of the preamble occurs,two adjacent transmissions of the preamble use the same beam and thepower ramping suspension instruction which is used to instruct the MAClayer by the physical layer is not received, adding 1 to the powerramping counter.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when the power ramping counteris configured based on a single beam and the beams are switched at eachretransmission, resetting the value of the power ramping countercorresponding to the current beam to that of the power ramping countercorresponding to a transmission beam, which is used to perform theprevious transmission of the random access preamble.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: obtaining a transmission powerof retransmission after ramping according to a formulaPREAMBLE_RECEIVED_TARGET_POWER=preambleInitialReceivedTargetPower+DELTA_PREAMBLE+(POWER_RAMPING_COUNTER−1)*powerRampingStep

where PREAMBLE_RECEIVED_TARGET_POWER denotes a target power value,preambleInitialReceivedTargetPower denotes an original power value,DELTA_PREAMBLE denotes a preset fixed value,

POWER_RAMPING_COUNTER denotes a value of the current power rampingcounter and powerRampingStep denotes a power ramping step size;

the power ramping step size is configured by the base station for theterminal or determined by a preset rule.

Optionally, when an obtained transmission power is larger than or equalsthe maximum power and when the computer programs are executed by theprocessor 301, following processing is implemented: transmitting therandom access preamble according to the maximum power.

Optionally, the at least two types of counters include: a preambleretransmission beam switching counter or a power level preambletransmission counter.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when beams are switched whenthe preamble is re-transmitted, adding 1 to the preamble retransmissionbeam switching counter or power level preamble transmission counter.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when the preambleretransmission beam switching counter or power level preambletransmission counter reaches a preset maximum number of times Max4 orMax4+1, then,

performing power ramping when re-transmitting the random access preambleand resetting the preamble retransmission beam switching counter orpower level preamble transmission counter;

at next retransmission of the random access preamble, keeping beamsun-switched; or

at the next retransmission of the random access preamble, switching to abeam, which has not been used to transmit the random access preamble, tore-transmit the random access preamble.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: an implementation mode ofswitching to the beam, which has not been used to transmit the randomaccess preamble, to re-transmit the random access preamble includes:

switching to a beam that is in a same power level or preset number ofpower levels with the current beam and has not been used to transmit therandom access preamble, to re-transmit the random access preamble.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when the preambleretransmission beam switching counter or power level preambletransmission counter reaches the maximum count value and a currenttransmission power of a terminal reaches the maximum transmission power,notifying an upper layer of a random access problem or failure of therandom access procedure via the MAC layer.

Optionally, when the computer programs are executed by the processor301, following processing is implemented: when a transmission power usedby a terminal for transmitting the preamble changes, resetting thepreamble retransmission beam switching counter or power level preambletransmission counter.

The terminal 300 may implement each process, which is implemented by theterminal in the above embodiment. In order to avoid repetition, theterminal is not repeated here.

The terminal in embodiments of the present disclosure counts a number oftimes of preamble retransmission and/or a number of times of powerramping of transmission of the preamble according to a configuredcounter/counters in random access procedure when detecting that the RARmessage is not correctly received or contention resolution fails.Therefore, the problem of being unable to simultaneously satisfy thefunctions of counting the power ramping and preamble transmission when asingle counter is used for counting both the power ramping and preambletransmission, can be avoided. With the mode in the embodiments of thepresent disclosure, the reliability of communication of the NR systemcan be guaranteed.

Each embodiment in the description of the embodiments is described in aprogressive manner. Each embodiment focuse on the differences with otherembodiments, and the same and similar parts among each embodiment can bereferred to each other.

A technical person in this field should understand that an embodiment ofthe present disclosure may be provided as methods, devices, or computerprogram products. Thus, the embodiments of the present disclosure maytake the form of a complete hardware embodiment, a complete softwareembodiment, or a combination of software and hardware embodiments.Further, the embodiments of the present disclosure may take the form ofa computer program product implemented on one or more computer availablestorage mediums (including, but not limited to, disk storage, CD-ROM,optical storage, etc.) containing computer available program codes.

Embodiments of the present disclosure are described by reference to themethods, terminal devices (systems), and the flow charts and/or blockdiagrams of the computer program products in embodiments of the presentdisclosure. It should be understood that each flow and/or block in theflowcharts and/or block diagrams and the combination of the flows and/orblocks in the flowcharts and/or block diagrams can be implemented bycomputer program instructions. These computer program instructions canbe provided to the general-purpose computers, special-purpose computers,embedded processors or processors of other programmable data processingterminal devices to assemble a machine, so that computers or theprocessors of other programmable data processing terminal devicesexecute instructions to implement one or multiple flows in the flowchart and/or devices of designated functions of one or multiple blocksof the block diagram.

These program instructions can also be stored in the computer readablestorage, which can boot the computers or other programmable dataprocessing terminal devices to work in a particular way, so thatinstructions stored in the computer readable storage generate amanufacture of an instruction device. The instruction device is used toimplement functions designated in one or multiple flows in a flow chartand/or one or multiple blocks in a block diagram.

The computer program instructions can be loaded into the computers orother programmable data processing terminal devices, so that a series ofoperations are executed on the computers or other programmable terminaldevices to provide the processing implemented by the computer.Therefore, instructions executed on the computers or other programmableterminal devices are used to implement steps of designated functions inone or multiple flows in the flow chart and/or in one or multiple blocksin the block diagram.

Although preferred embodiments of the present disclosure have beendescribed, technical personnel in the field may make additional changesand modifications to these embodiments once the basic creative conceptsare known. Therefore, the attached claims are intended to be interpretedas including the preferred embodiments and all changes and modificationsfalling within the scope of the embodiments of the present disclosure.

It should be noted that, in the present disclosure, relational termssuch as first and second are used only to distinguish one entity oroperation from another and do not necessarily require or imply any suchactual relationship or order between these entities or operations.Further, the term of “include”, “comprise” or any variation thereof isintended to cover a non-exclusive contain. Therefore, processes,methods, materials and devices, which include a series of elements, notonly include the elements, but also include other elements, which arenot listed, or further include inherent elements of the processes,methods, materials and devices. In the absence of more restrictions, theelements defined by a statement “includes one ” do not exclude that theprocesses, methods, materials and devices, which include these elements,also include additional same elements.

The foregoing only describes preferred embodiments of the presentdisclosure. It should be noted that an ordinary skilled in the art ofthe present disclosure can make any change or improvement made withoutdeparting from the principle of the present disclosure. These changesand improvements are also covered by the protection scope of the presentdisclosure.

What is claimed is:
 1. A method for counting preamble retransmission ina random access procedure, comprising: in a random access procedure,when detecting that no Random Access Response (RAR) is received orcontention resolution fails, counting a number of times ofretransmission of a preamble and/or a number of times of power rampingof transmission of the preamble according to a configuredcounter/counters.
 2. The method according to claim 1, wherein theconfigured counter/counters comprises: the counter of one type; and themethod further comprises: when the RAR message is not correctly receivedor the contention resolution fails, adding 1 to the counter; or when theRAR message is not correctly received or the contention resolution failsand a power ramping suspension instruction which is used to instruct aMedium Access Control (MAC) layer by a physical layer is not received,adding 1 to the counter.
 3. The method according to claim 2, wherein thecounter/counters comprises: a preamble transmission counter.
 4. Themethod according to claim 3, wherein when a count value of the preambletransmission counter reaches a first preset maximum number of times oftransmission Max1 or Max1+1, the method further comprises: notifying anupper layer of a random access problem or failure of the random accessprocedure via the MAC layer.
 5. The method according to claim 3, furthercomprising: when the preamble transmission counter counts preambleretransmission, when two adjacent transmissions of the preamble use asame beam, adding one step size to a transmission power; or when the twoadjacent transmissions of the preamble use the same beam and the powerramping suspension instruction which is used to instruct the MAC layerby the physical layer is not received, adding one step size to thetransmission power; otherwise, keeping the transmission power unchanged;wherein the step size is configured by a base station for a terminal ordetermined according to a preset rule.
 6. The method according to claim5, wherein when an obtained transmission power is larger than or equalsa maximum transmission power, the method further comprises:transmitting, by the terminal, the random access preamble according tothe maximum transmission power. 7-17. (canceled)
 18. The methodaccording to claim 2, wherein the counter/counters comprises a powerramping counter.
 19. The method according to claim 18, furthercomprising: when any of not correctly receiving the RAR message inpreset time, contention resolution failure and retransmission of thepreamble occurs and two adjacent transmissions of the preamble use asame beam, adding 1 to the power ramping counter; or when any of notcorrectly receiving the RAR message in the preset time, contentionresolution failure and retransmission of the preamble occurs, twoadjacent transmissions of the preamble use the same beam and the powerramping suspension instruction which is used to instruct the MAC layerby the physical layer is not received, adding 1 to the power rampingcounter.
 20. The method according to claim 18, further comprising: whenthe power ramping counter is configured based on a single beam and thebeams are switched at each retransmission, resetting a value of thepower ramping counter corresponding to the current beam to a value ofthe power ramping counter corresponding to a transmission beam, which isused to perform the previous transmission of the random access preamble.21. The method according to claim 18, further comprising: obtaining atransmission power of retransmission after ramping according to aformulaPREAMBLE_RECEIVED_TARGET_POWER=preambleInitialReceivedTargetPower+DELTA_PREAMBLE+(POWER_RAMPING_COUNTER−1)*powerRampingStep; whereinPREAMBLE_RECEIVED_TARGET_POWER denotes a target power value,preambleInitialReceivedTargetPower denotes an original power value,DELTA_PREAMBLE denotes a preset fixed value, POWER_RAMPING_COUNTERdenotes a value of the current power ramping counter andpowerRampingStep denotes a power ramping step size; the power rampingstep size is configured by a base station for a terminal or determinedby a preset rule.
 22. The method according to claim 21, wherein when atransmission power obtained via calculation is larger than or equals amaximum power, the method further comprises: transmitting, by theterminal, the random access preamble according to the maximum power.23-29. (canceled)
 30. The method according to claim 1, wherein theconfigured counter/counters comprise: at least two types of counters;the method further comprises: when the counters reach a maximum numberof times, notifying an upper layer of a random access problem or failureof the random access procedure via the MAC layer. 31-36. (canceled) 37.The method according to claim 30, wherein the at least two types ofcounters comprise: a preamble transmission counter and a power rampingcounter.
 38. The method according to claim 37, further comprising: whenthe RAR message is not correctly received in preset time or thecontention resolution fails, adding 1 to the preamble transmissioncounter.
 39. The method according to claim 37, wherein when a countvalue of the preamble transmission counter reaches a first presetmaximum number of times of transmission Max1 or Max1+1, the methodfurther comprises: notifying an upper layer of a random access problemor failure of the random access procedure via the MAC layer.
 40. Themethod according to claim 37, further comprising: when the preambletransmission counter counts preamble retransmission, when two adjacenttransmissions of the preamble use a same beam, adding one step size to atransmission power; or when the two adjacent transmissions of thepreamble use the same beam and the power ramping suspension instructionwhich is used to instruct the MAC layer by the physical layer is notreceived, adding one step size to the transmission power; otherwise,keeping the transmission power unchanged; wherein the step size isconfigured by a base station for a terminal or determined according to apreset rule.
 41. The method according to claim 37, further comprising:when any of not correctly receiving the RAR message in preset time,contention resolution failure and retransmission of the preamble occursand two adjacent transmissions of the preamble use a same beam, adding 1to the power ramping counter; or when any of not correctly receiving theRAR message in the preset time, contention resolution failure andretransmission of the preamble occurs, two adjacent transmissions of thepreamble use the same beam and the power ramping suspension instructionwhich is used to instruct the MAC layer by the physical layer is notreceived, adding 1 to the power ramping counter.
 42. (canceled)
 43. Themethod according to claim 37, further comprising: obtaining atransmission power of retransmission after ramping according to aformulaPREAMBLE_RECEIVED_TARGET_POWER=preambleInitialReceivedTargetPower+DELTA_PREAMBLE+(POWER_RAMPING_COUNTER−1)*powerRampingStep; whereinPREAMBLE_RECEIVED_TARGET_POWER denotes a target power value,preambleInitialReceivedTargetPower denotes an original power value,DELTA_PREAMBLE denotes a preset fixed value, POWER_RAMPING_COUNTERdenotes a value of the current power ramping counter andpowerRampingStep denotes a power ramping step size; the power rampingstep size is configured by a base station for a terminal or determinedby a preset rule.
 44. The method according to claim 43, wherein when atransmission power obtained via calculation is larger than or equals amaximum power, the method further comprises: transmitting, by theterminal, the random access preamble according to the maximum power.45-101. (canceled)
 102. A terminal, comprising: a storage, processor andcomputer programs which are stored in the storage and run on theprocessor; wherein the computer programs are executed by the processorto implement the method for counting preamble retransmission in therandom access procedure according to claim
 1. 103. (canceled)